Step by step: Get back a lot of disk space from Vista (ShadowStorage resizing)

Many people complain over disk space missing in Vista. By time you end up with 5, 10 or more GB missing on large volumes for no obvious reason. Why? Well Vista is playing safe - everytime you, or system changes something on disk, Vista can make a shadow copy of the content that was changed. That ensures backward compatibility, restore points, driver rollback etc... If you really want to know there is a service called Volume Shadow Copy Service running in the background that makes those copies. They are put into the winsxs folder in your Windows folder and size of that Shadow Storage is unfortunately determined when you install Vista. Meaning it was calculated at the time when you had only Vista on the disk. That logic ends up in quite large storage sizes that are responsible for eating huge chunks of your disk space.

Even worse situation is with multiple disk volumes. You can end up with lots of GB missing on a large volume with Steam folder for example. In my case it was 8 GB on a 30 GB volume. For what? Old versions of gcf files? No thanks!

So lets do something about it.

1. Press Start
2. Type cmd in the search field
3. Rightclick on the cmd.exe that was found and choose Run as administrator
4. Type vssadmin list shadowstorage

Here you can check how much of your disks are used for shadow storage.

You would usually find some big numbers for the C: volume or volume where Steam resides.

You can fix it by typing something like this:
5. vssadmin resize shadowstorage /For=C: /On=C: /MaxSize=3GB

It will remove your current restore points BTW! Don't worry - restore points will be recreated again in the future.

/for determines which volume will be shadowed
/on determines where the shadow will be placed, yes you can move it to other volumes, but I haven't tried it.
/maxsize determines the size of the shadow storage. It understands MB, GB etc... Minimum number is 300MB.

For normal Vista operation and some reasonable restore points you would need around 3-5 GB at most for c:, on c: for example. Other volumes don't need to be shadowed more than minimum which is exactly 300MB. if you have C: only, it is quite straightforward.

This procedure doesn't kill anything in Vista except current restore points and some old drivers for devices that you usually update a lot like graphics drivers. All Vista restore, rollback, backup etc... functionalities will be intact. It doesn't touch your pagefile.sys or anything - just gives less room for the above mentioned service to store old (changed) files on your disk.

In my case I got around 6 GB on C:, 4 GB on D: and 8 on my E: disk with Steam. I had 100GB disk - that is 18%.

6. Defragmentation after resize
I highly recommend the built in Vista defragmenter (yeah I know all about other defragmenters, but this time this one does the job better) after this resize, since it will rearrange and compress many Vista files and make even more room along with the defragmentation. It is worth leaving your comp for a couple of hours defragmenting for this once. Please do check and clean disk beforehand - using CCleaner or Vista Disk Cleanup.

If you do this procedure, please report your free space before and after resizing, and defragmenting.

Of course you can enlarge the shadow storage space if you want/need and end up in even less disk space in a couple of days!

If I made some mistake or forgot something, please reply so I can edit the post. Additional info can be found here: http://bertk.mvps.org/html/diskspacev.html

Cheers,

Ivan